Field of the Invention
In the pursuit of economic and environmentally responsible electrical energy generation, a multitude of processes have been proposed for converting the kinetic energy of moving water to electrical energy. A major issue concerning hydrokinetic generation devices is how to achieve economically feasible conversion efficiency without sacrificing environmental integrity. Early proposals for hydrokinetic turbine converters have been largely hampered by the significant environmental risk that rotating windmill-style turbine blades pose. Additionally, spiral turbine proposals have largely failed to achieve a high enough conversion efficiency to make them economically feasible. Thus, known hydrokinetic turbine converter devices have largely not been viable.
Significant environmental issues have arisen in regards to the operation of hydrokinetic turbines. Hydrokinetic turbines impact the environment through both their mode of operation and the volume of space that they occupy. The rotation of a windmill-style turbine blade poses a direct threat to wildlife through its operation. Although, the inherent operation of a spiral turbine blade does not pose a significant environmental risk, the devices often require a large volume of water in order to achieve economic viability. Due to these environmental issues, support of hydrokinetic turbine generators by environmentally concerned groups and local communities has not been undisputed.
A limiting factor for hydroelectric generation via spiral turbine blade is the volume of moving water and space that the device must utilize in order to achieve economic feasibility. It is therefore advantageous for a hydrokinetic spiral turbine blade that is capable of augmenting the conversion efficiency of the spiral turbine blade, thereby decreasing environmental impact while increasing electrical energy output, and thus making the spiral turbine blade economically viable.
Description of Related Art
Efforts have been made to augment the conversion efficiency of the spiral turbine blade. U.S. Pat. No. 7,938,622 B2 to Anderson discloses a dually tapered helical auger turbine with a perpendicular flange on the blade. The device is capable of generating electricity from multi-directional fluid flows. Additionally, it utilizes pressurized fluid in order to store energy, which can be released during slow output periods to maintain a generally constant electrical supply.
U.S. Patent 20120076656 A1 to Abass discloses a logarithmic spiral turbine blade, which is an improvement on the spiral turbine blade providing augmented conversion efficiency through improved blade design. Although the above specified prior art largely improves the conversion efficiency of the spiral turbine blade, it does not address the problem of failing to utilize those velocity vectors of the moving fluid which are moving generally parallel to the spiral turbine blade.
Hydroelectric generation systems which utilize an induced vortex to improve the conversion efficiency of the apparatus are known. U.S. 20080238105 A1 to Ortiz, Baca, and Wichers discloses a hydrokinetic turbine which utilizes an intake shroud with fixed helical vanes to induce a moving fluid into a vortex before it drives the rotation of a turbine. U.S. Pat. No. 8,764,391 B2 to Smith and Otte discloses a hydrokinetic windmill-style turbine generator that utilizes vortex-inducing blades within an intake shroud to produce a rifling effect on the water stream before it drives the rotation of the turbine blades for electrical production, thereby augmenting conversion efficiency. Although utilizing vortex-inducing apparatuss to augment conversion efficiency are known in the prior art, the problem of capturing the velocity vectors aligned by the induced vortex via spiral turbine blade is not fully addressed.
Prior art which utilizes a modified spiral turbine blade design in order to augment conversion efficiency are known. Patent DE102012016202 A1 to Tischner and Siglbauer describes a spiral turbine blade with profiles to capture an increased amount of hydrokinetic energy, thereby improving the conversion efficiency. Additionally, U.S. patent U.S. 20120242088 A1 to Raz and Eyal describes at least one conical spiral for hydroelectric generation. Patent WO 2001086120 A1 to Marie Claire De Vriendt discloses a spiral turbine blade that utilizes discrete steps to augment the conversion efficiency of the spiral turbine blade. Prior art which increases the range of velocity vectors powering the rotation of a spiral turbine bade are known. However, the prior art does not address the improved utilization of those velocity vectors aligned in a vortex. The prior art does not fully address the conversion efficiency problem, and a spiral turbine blade utilizing concave compartments for capture and channeling of velocity vectors aligned via vortex-inducing apparatus, such as spiral depressions on a conical intake shroud, provides novel improvement to the spiral turbine blade as a hydroelectric generation apparatus.
Although spiral turbine blades which utilize induced vortices and spiral turbine blades which augment conversion efficiency via improved design are known in the prior art, the problem of maximizing conversion efficiency has not been fully addressed and further design improvements are desired for economic viability of the apparatus. The disclosed spiral turbine blade having at least one concave compartment addresses the conversion efficiency problem by utilizing a design which captures and channels an increased range of velocity vectors of a moving fluid, specifically those aligned in an induced vortex, thereby augmenting the conversion efficiency of the spiral turbine blade.